Question 4
Which of the following would be considered a form of active transport?
o the movement of oxygen molecules from high concentration in the blood to low concentration in the cell.
O the movement of carbon dioxide from high concentrations in the cell to low concentrations in the blood.
o the movement of glucose into the cell down its concentration gradient,
o the movement of sodium atoms from low concentration in the cell to higher concentrations outside the cell.
D. A duck flies to another pond.
The above sentence is an example of emigration. Emigration refers to moving from one area to another for a long or permanent period. In this instance, a duck is leaving the pond it originally resided in (along a population other ducks) in order to reside in another pond. Therefore, it can be said that the duck "emigrated".
<em>A </em><em>virus </em><em>is an agent that causes infections and diseases.
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<h2>Further Explanation
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Viruses are microscopic parasites that infect cells of biological organisms. Viruses are obligate parasites, this is because viruses can only reproduce in living material by invading and utilizing the cells of living things because viruses do not have cellular equipment to reproduce themselves.
The term virus usually refers to particles that infect eukaryote cells (multicellular organisms and many types of single-cell organisms), while the term bacteriophage or phage is used for types that attack types of prokaryotic cells (bacteria and other organisms that do not cell nucleated).
The virus has been infecting since the days before Christ, this is evidenced by the existence of several discoveries, namely reports of virus infections in hieroglyphics in Memphis, the capital of ancient Egypt (1400 BC) which shows the existence of poliomyelitis. In addition, King Pharaoh Ramses V died in 1196 BC and is believed to have died of the smallpox virus.
In 1880, Louis Pasteur and Robert Koch put forward a "germ theory" namely that microorganisms are the cause of disease. At that time also the famous Koch Postulate which is very well known today, namely:
- A disease agent must be present in every case of the disease
- The agent must be isolated from the host and can be grown in vitro
- When the muri agent culture is inoculated into susceptible healthy host cells, it can cause disease
- The same agent can be taken and re-isolated from the infected host
<h3>Various kinds of viral infections
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- Acute infections are infections that last for a short time but can also be fatal.
- Chronic infection is a prolonged viral infection so there is a risk of symptoms of the disease coming back.
Learn More
Viruses brainly.com/question/11690598
The infection by virus brainly.com/question/8633233
Details
Class: Middle School
Subject: Biology
Keywords: viruses, disease, infection
When the influenza virus enters an epithelial cell, the infected cell responds by posting antigens and acting as a flag for cytotoxic T cells.
<h3>What is the cell-mediated response?</h3>
The cell-mediated response is a type of immune response where the organism is able to respond to pathogens by immune cells.
Macrophages (as well as other immune cells ) can act during cell-mediated immune responses.
In conclusion, when the influenza virus enters an epithelial cell, the infected cell responds by posting antigens and acting as a flag for cytotoxic T cells.
Learn more about cell mediated responses here:
brainly.com/question/24378503
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